TVC E. Nigerian anti-drug officers found 9.15 kg (20 pounds) of cocaine worth $4.7 million “factory-packed”inside a new pair of shoes that arrived at Abuja airport on a flight from Brazil, authorities said on Tuesday.

It was Nigeria’s biggest drug seizure of 2016. West African nations are often used as transit points by gangs moving drugs between South America and Europe.

Nigeria’s NDLEA drug enforcement agency said a 34-year-old Nigerian motorcycle parts dealer was arrested after the discovery of the cocaine during a screening of passengers and luggage arriving on a flight from Sao Paulo.

“It is our single biggest seizure of cocaine in the last year. We have had bigger seizures of methamphetamine but for cocaine this is a big seizure. And the mode of containment was ingenious. It was a factory-packed concealment because they were brand new footwear,” NDLEA spokesman Ofoyeju Mitchell said.